1. Field of the Invention
The present invention relates to a portable GPS position measuring/displaying apparatus which can be put in a pocket and easily carried at all times. More specifically, the present invention relates to a portable GPS position measuring/displaying apparatus which is suitable for use in leisure activities (such as hiking, orienterring, travel, mounting climbing, and cycling), business, and events for women and children, and which enables the user to easily confirm the present position or destination and is therefore useful in preventing lost children in emergency.
2. Description of the Related Art
FIG. 1 is a perspective view showing a portable GPS position measuring/displaying apparatus for automobiles, which is conventionally known as a car navigation system.
Referring to FIG. 1, reference numeral 1 denotes a car computer unit. A GPS receiver, a display processor, a CD-ROM player, an internal/external signal processing unit, etc. are arranged inside the car computer unit. A GPS antenna 2 and a liquid crystal display 3 are connected to the car computer unit 1 by means of cables 5a and 5b. A key operation commander 4 sends instructions or commands to the car computer unit 1 and/or the liquid crystal display 3 by radio.
A conventional portable GPS position measuring/displaying apparatus for automobile is made up of a number of independent structural components (the apparatus mentioned above is made up of four independent components), and each of these components is comparative large in size. Therefore, the conventional portable GPS position measuring/displaying apparatus is not appropriate for use as a portable type. In addition, the conventional portable GPS position measuring/displaying apparatus consumes a comparatively large amount of power and must employ a battery of high capacitance. In light of this point as well, the conventional apparatus is not suitable for use as a portable type. It should be also noted that the conventional apparatus is expensive as a whole.
Accordingly, an object of the present invention is to provide:
(a) a portable GPS position measuring/displaying apparatus which is small in size and light in weight and which is suitable for use as a portable apparatus; PA1 (b) a portable GPS position measuring/displaying apparatus which can be manufactured at a very low cost, which is at least one half of the cost needed for manufacturing a conventional apparatus; and PA1 (c) a portable GPS position measuring/displaying apparatus which enables accurate correction of the time of a timepiece used for calculating the present position from navigation data, and which enables the user to know the correct standard time whenever necessary. PA1 a portable case; PA1 a liquid crystal display provided for the portable case; PA1 operation keys of a variety of kinds which are provided on the case; PA1 a map storage card detachably inserted in the portable case; and PA1 a multi-layered printed circuit board inserted in the portable case, the printed circuit board including: a patch type GPS antenna for receiving GPS waves from an artificial satellite; a GPS receiver made of an LSI which processes information represented by the received GPS waves so as to produce position data of an object to be measured; an operation device for calculating the position where the object to be measured is present on the basis of the position data; and display means for displaying the calculated position of the object on the screen of the liquid crystal display such that the calculated position is superimposed on map data read from the map storage card.